Burglar-alarm.



R. & J. NEIL'soN.

BURGLAR ALARM.

' APPLICATION Hmm` Junin, 1909 4 l 991,741 Patented May 9,1911.

1HE :mums PETERS ca.. wxsnmcrow, A c4 ROBERT NEILSON AND JAMES NEILSON, OF NEW YORK, N. Y.

BURGLAR-ALARM.

Application led .Tune 12,

To all whom it may concern; i

Be it known that we, ROBERT NEILsoN and JAMES NmLsoN, citizens of the United States, residing in the city, county, and State of New York, have invented certain new and useful Improvements in Burglar- Alarms, of which the following is a speciication.

Our invention relates to burglar alarms and has for its object the provision of spring motor alarm secured to a swinging door or window and provided with release mechanism consisting of a spring controlled lever that engages a pin on the main gear wheel of the motor to hold the motor from operation, and a catch secured on the casing to engage said lever when the door is opened to release the lever from engagement with the pin on the main gear wheel, and the alarm sounds until the gear wheel makes a complete rotation. The catch on the frame consists of a housing having a spring actuated bolt therein with its protruding end beveled on its outer side to admit of the lever on the alarm pressing it back when closing the door. A plate is also pivotally mounted on the housing of the catch that is adapted to be swung in front of the end of the bolt to hold it in an inoperative position.

Our invention will be described in detail hereinafter and illustrated in the accompanying drawings in which Figure 1 is a front view of a fragment of a door and casing showing our improved alarm in position thereon and the alarm mechanism and catch in position. Fig. 2, a side view of the bell and catch partly in section, Fig. 3, an end view of the catch, and Fig. t a fragmental view showing the alarm mechanism released.

In the drawings similar referencevcharacters indicate corresponding parts in allv of the views.

A indicates a swinging door and B its casing. The alarm consists of a base 1 secured to door A on which is secured a. spring motor 2 geared to an escapement wheel 3.

4 indicates a bell clapper secured to a shaft 5 on which is also secured the escapement anchor 6.

The end of the main shaft 7 of the motor 2 is threaded and the bell 8 is provided wit-h a threaded boss 9 on its interior to engage said threaded end of the shaft, said shaft being so threaded that as the bell is Specification of Letters Patent.

rotated in one direction the main spring of Patented May l9, 1911.

1909. Serial No. 501,820.

the motor is wound up, and may be removed by rotating it in the other direction.

10 indicates a lever fulcrumed on ears 11 secured to base 1, the inner end of the lever engaging' a pin 12 on the main gear wheel 13 of the motor 2, while its other end projects outside of the base 1 and is formed with the side toward the door beveled as shown at 14.

15 indicates a leaf spring secured to the base and engaging the underside of lever 10 to hold it normally in the position to engage the pin 12 and to return it to said position by the instrumentalities hereinafter described.

16 indicates a catch secured to the casing B consisting of a housing 17 and a spring actuated bolt 18 slidably mounted therein and adapted to engage the project-ing end of lever 10, theouter side of the protruding end of bolt 18 being beveled as shown at 18a so that the door may be closed when open, the beveled surfaces 14: of lever 10 and 18a of bolt 18 operating to move the bolt back against the resistance of the spring, but when the door is closed it can not be opened when the bolt 18 is in an operative position without swinging the inner end of said lever 10 out of engagement with pin 12 and releasing the motor 2 so that the bell is sounded during one rotation of gear wheel 13, or until the pin 12 again engages the lever 10, which is returned to its normal position immediately after passing the end of bolt 18 by means of spring 15. h

19 indicates a' plate swivelly mounted on the front end of housing 17 and arranged to be swung in front of the end of bolt 18 when it is desired to hold said bolt in an inoperative position so that the door A may be opened without operating the alarm.

Having thus described our invention what we claim is- 1. In a burglar alarm, a spring motor bell, the main gear wheel of the motor having a pin secured thereto, a lever suitably fulcrumed and moving in a plane perpendicular to the main gear wheel, said lever normally engaging said pin to hold the gear wheel from rotation, and a catch to engage said lever and move it from engagement with the pin.

2. In combination with a door and casing, an alarm secured to the door, and a catch for operating the alarm consisting of a housing, a spring-actuated bolt mounted in the housing, and a plate sWivelly mounted on the housing and adapted to be lnoved in 'i'ont of the bolt to hold it out of an operative position.

3. In combination with a door and its oasing, a spring inotoi1 bell secured to the door, the inain gen11 Wheel of said inotor having a pin secured thereto, u spring-Controlled lever suitably fulcluined on the dooi1 and noilnally engaging said pin, a housing secured to the casing, a spring actuated bolt mounted in Suid housing und adapted to engage the lever and 1nove it from engagement with said pin, und a plate swivelly secured to said housing and adapted to be lnoved in front of the bolt to hold it out of an operative position.

In testimony whereof We hereto aiX our signatures in the presence of two Witnesses.

ROBERT NELSON. JAMES NEILSON. Witnesses EUGENE A. CAssoT, LOUIS SHWITZER.

Copies of this patent may be obtained for five cents each, by

addressing the Commissioner of Eatents,

Washington, D. C. 

